mat-surface-adsorption: site labels show as "unknown" — result.get("site") should be result.get("adsorption_site") #49

In .agents/skills/mat-surface-adsorption/scripts/calculate_adsorption.py (line 120):

site_info = result.get("site", "unknown")

This causes every entry in adsorption_results.json to report "site": "unknown".

Root cause

In matcalc 0.5.1, AdsorptionCalc.calc_adslabs stores the site label in each
adslab dict under the key "adsorption_site" (alongside "adsorption_site_coord"
and "adsorption_site_index"), and these keys pass through calc_many into the
returned results. The script looks up "site", which does not exist, so the
fallback "unknown" is always used.

Suggested fix

site_info = result.get("adsorption_site", "unknown")

Optionally also record "site_coord": result.get("adsorption_site_coord", None)
in the output JSON for traceability.

Verification

Tested with MACE-OMAT-0-small on CO/Cu(111) (matcalc 0.5.1, CPU). After the
one-word change, the JSON correctly reports 1 ontop + 1 bridge + 2 hollow sites,
with the most stable site being ontop (E_ads = -0.506 eV), consistent with
literature.